Field of the Invention
The present invention relates to a driving module and a lens driving device using the same, and more particularly to an electromagnetic driving module which converts electrical energy into mechanical energy, and a lens driving device using the same.
Description of the Related Art
Some electronic devices are equipped with a driving module to drive an element to move a predetermined distance. For example, a lens driving device in a camera usually includes a driving module to generate motive power. One or more optical lens units of the lens driving device are driven by the motive power to move along a direction perpendicular to an optical axis, so as to facilitate image stabilization.
However, since the driving module includes a complex driving member, such as a stepper motor, ultrasonic motor, piezoelectric actuator, etc. to generate the motive power, and the motive power has to be transmitted by a number of transmission elements, it is not easy to assemble and the manufacturing cost is high. In addition, a conventional driving module is also large in size and has high power consumption due to its complex construction.
On the other hand, in the driving module described above, a movable portion for carrying a lens is usually connected to a fixed portion by a plurality of suspension wires. The suspension wires extend in a direction that is parallel to the optical axis of the lens to facilitate the movement of the movable portion in a direction that is perpendicular to the optical axis with respect to the fixed portion.
However, the arrangement of the suspension wires will be detrimental to the reduction of the thickness of the driving module because the elastic coefficient of the suspension wires in the direction that is perpendicular to the optical axis increases as its length decreases, and the movable portion cannot be stably moved relative to the fixed portion if the length of the suspension wires is reduced.